Why don't population experts blame their wrong predictions?

Demographers are not responsible for their prediction errors for the following reasons:

1. Population development is a complex process, which is influenced by many factors, such as fertility rate, mortality rate and migration. It is difficult to predict and has high uncertainty.

2. Population development is also influenced by political, economic and social factors, and the changes of these factors may lead to the deviation of population development.

3. Population forecasting models and methods are constantly improving and perfecting, and different models and methods may get different forecasting results.